A music player has sequencers each including a reading and restoring function unit for reading music information including header information, a delta time, and a message and restoring running status of the message; a message analyzing and processing function unit for analyzing the header information, consuming a period of time according to the delta time, and processing the message to generate sound source drive information; a writing function unit for writing the sound source drive information into an output memory; and a sequencer controlling function unit for controlling the reading and restoring function unit to read and restore the music information, controlling the message analyzing and processing function unit to analyze the header information, and controlling the message analyzing and processing function unit and the writing function unit to consume the period of time, generate the sound source drive information, and write the sound source drive information.
1. A music player comprising:
a plurality of sequencers to be switched for playing music in a plurality of channels, each of said plurality of the sequencers including,
a reading and restoring function unit for reading music information including header information, a delta time, and a message from an input memory and restoring running status of the message;
a message analyzing and processing function unit for analyzing the header information input from the reading and restoring function unit, consuming a period of time according to the delta time, and analyzing and processing the message to generate sound source drive information;
a writing function unit for writing the sound source drive information generated in the message analyzing and processing function unit into an output memory; and
a sequencer controlling function unit for controlling the reading and restoring function unit to read and restore the music information, controlling the message analyzing and processing function unit to analyze the header information, and controlling the message analyzing and processing function unit and the writing function unit to consume the period of time, generate the sound source drive information, and write the sound source drive information, respectively, when the header information is normal, wherein
when said plurality of the sequencers is switched, a part or a whole part of an operational state of each of the reading and restoring function unit, the message analyzing and processing function unit, the writing function unit, and the sequencer controlling function unit is maintained per said each of the reading and restoring function unit, the message analyzing and processing function unit, the writing function unit, and the sequencer controlling function unit while said each of the reading and restoring function unit, the message analyzing and processing function unit, the writing function unit, and the sequencer controlling function unit stops operating.
2. A music player according to claim 1 , wherein said reading and restoring function unit in one of the plurality of the sequencers maintains information distinguishing the header information, the delta time, and the message, and an amount of data that the reading and restoring function unit has read as the operational state thereof when the one of the plurality of the sequencers stops operating while the reading and restoring function unit is reading the music information.
3. A music player according to claim 2 , wherein said reading and restoring function unit maintains a type of the message as the operational state thereof when the music information is the message while the reading and restoring function unit is reading the music information.
4. A music player according to claim 2 , wherein said sequencer controlling function unit maintains information distinguishing operations of reading the header information, reading the delta time, and reading the message as the operational state thereof.
5. A music player according to claim 1 , wherein said message analyzing and processing function unit in one of the plurality of the sequencers maintains information indicating that the message analyzing and processing function unit is consuming the period of time and a consumed time as the operational state thereof when the one of the plurality of the sequencers stops operating while the message analyzing and processing function unit is consuming the period of time.
6. A music player according to claim 5 , wherein said sequencer controlling function unit maintains information indicating that the sequencer controlling function unit is controlling timing as the operational state thereof.
7. A music player according to claim 1 , wherein said sequencer controlling function unit in one of the plurality of the sequencers maintains information indicating that the writing function unit is writing the sound source drive information as the operational state thereof when the one of the plurality of the sequencers stops operating while the writing function unit is writing the sound source drive information.
8. A music player according to claim 1 , wherein said reading and restoring function unit further includes a function unit for converting a format of the music information to another format compatible with the message analyzing and processing function unit.